Advanced Search

Normalize telephone numbers

/ Published in: PHP
Save to your folder(s)
This snippet is usable for telephone number normalization. It supports re-mapping of misused alphabetical characters (e.g. i for 1) and some other clean up stuff... Take a look.

Update, 2009-10-02: added function to create a corresponding MySQL REPLACE construct to normalize data which is already stored in database. I decided to use this approach because MySQL's regular expression engine is very slow. TODO: add the possibility to remove non digit characters at the end of the laaaarge REPLACE call.

Expand | Embed | Plain Text

Copy this code and paste it in your HTML 
  1. <?php
  2.   $search_replace_mapping = array(
  3.     // country prefix normalization
  4.     '+00' => '+', '++' => '+',
  5.     // country prefix is always 00
  6.     '+' => '00',
  7.     // funny user input goulash
  8.     'i' => '1', 'I' => '1', 'l' => '1',
  9.     'o' => '0', 'O' => '0',
  10.  
  11.     // ([^\diIloO\+]*)
  12.     // ...brackets
  13.     '(' => '', ')' => '',
  14.     '[' => '', ']' => '',
  15.     '[' => '', ']' => '',
  16.     // slashes
  17.     '/' => '', '\\\\' => '',
  18.     // dashes
  19.     '-' => '', '_' => '',
  20.     // whitespaces
  21.     ' ' => ''
  22.   );
  23.  
  24.   function normalizeTelephoneNumber($telephone_number, $search_replace_mapping) {
  25.     // fetch search and replace arrays
  26.     $search = array_keys($search_replace_mapping);
  27.     $replace = array_values($search_replace_mapping);
  28.  
  29.     // simple string replacement
  30.     $telephone_number = str_replace($search, $replace, $telephone_number);
  31.  
  32.     // lets kick out all dutty stuff which is left...
  33.     $telephone_number = preg_replace('~[^\d]~', '', $telephone_number);
  34.  
  35.     return $telephone_number;
  36.   }
  37.  
  38.   function generateSqlReplaceStatement($telephone_number, $search_replace_mapping)
  39.   {
  40.     $s = '';
  41.     $template = 'REPLACE(%s, \'%s\', \'%s\')';
  42.  
  43.     $i = 0;
  44.     foreach ($search_replace_mapping as $search => $replace)
  45.     {
  46.       $s = sprintf($template, ($i == 0 ? '\''. $telephone_number .'\'' : $s), $search, $replace);
  47.       $i++;
  48.     }
  49.  
  50.     $s = 'SELECT '. $s .' AS normalized FROM Accommodation';
  51.  
  52.     return $s;
  53.   }
  54.  
  55.   $numbers = array(
  56.     '0049 03831 667 156',
  57.     '+39 0471 / 975     642',
  58.     '+0039 6757 - 3939 9393',
  59.     '+49 (0) 3834 50 77 73',
  60.     '+43 (i) 4m 4n idiOt',
  61.     '+44 (0) 1234 \\ 55 55'
  62.   );
  63.  
  64.   print_r($numbers);
  65.  
  66.   $numbers_clean = array();
  67.   foreach ($numbers as $number)
  68.   {
  69.     $numbers_clean[] = normalizeTelephoneNumber($number, $search_replace_mapping);
  70.   }
  71.  
  72.   print_r($numbers_clean);
  73.  
  74.   $sql = array();
  75.   foreach ($numbers as $number)
  76.   {
  77.     $sql[$number] = generateSqlReplaceStatement($number, $search_replace_mapping);
  78.   }
  79.  
  80.   print_r($sql);
  81. ?>

Report this snippet


Comments

RSS Icon Subscribe to comments

You need to login to post a comment.